JPH08216403A - Inkjet recording method - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent flight deflection of ink droplets peculiar to ink jet recording ink having high penetrability and capable of obtaining a high-quality recorded image on plain paper. An inkjet recording method for recording by ejecting ink droplets from a nozzle opening 2 of a nozzle plate 3 provided with an ink repellent coating layer 1 by driving a piezoelectric vibrator 8, at least (A) Nozzle openings 2 when not ejected using an inkjet recording ink containing a dye, (B) glycol ether having a solubility in water of less than 10% at room temperature, and (C) an organic solvent soluble in water
The piezoelectric vibrator 8 is driven by a drive voltage that does not eject ink droplets from the.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording method using an ink jet recording ink capable of obtaining a high quality recording image on plain paper, and more specifically, to an ink droplet ejected from a nozzle opening. The present invention relates to an inkjet recording method that is effective in preventing flight bending and that can obtain a good recorded image.

[0002]

2. Description of the Related Art Ink jet recording is the recording of information on a recording medium by ejecting minute ink droplets from nozzle openings. Therefore, stable ejection of the ink droplets is a necessary condition for accurately recording the transmitted information on the recording medium. However, due to the wetting of the ink around the nozzle openings, the ejection direction of the ink droplets may be incorrect. It has a problem of becoming stable. To solve this problem, Japanese Patent Laid-Open No. 57-
In the nozzle plate disclosed in Japanese Patent No. 107848, an ink-repellent coating layer such as a fluororesin is uniformly formed on the inner surface of the nozzle and the surface of the nozzle plate by sputtering to suppress the wetting of the ink around the nozzle opening. It is a thing. U.S. Pat. No. 4,296,421 also considers applying a water-repellent treatment or an oil-repellent treatment to the periphery of the nozzle opening and a part of the inner surface. In this way, by providing the ink-repellent coating layer on the nozzle plate, it has been devised to prevent ink bleeding and ink leakage to the nozzle plate, and to stabilize the ejection direction of ink droplets.

Further, in order to obtain a high-quality recorded image, ink jet recording ink is required to have characteristics such as good drying property on a recording medium and no bleeding. A particular problem here is when paper is used as the recording medium. Since the fibers of paper have non-uniform wettability, dots with high roundness cannot be obtained, and bleeding easily occurs.

In the conventional ink for ink jet recording,
In order to improve the permeability of the recording medium, diethylene glycol monobutyl ether may be added as in US Pat. No. 5,156,675, or US Pat. No. 5,183.
Surfactant surfynol 465 may be added as described in US Pat. No. 502, or US Pat.
As described in Japanese Patent No. 56, addition of both diethylene glycol monobutyl ether and Surfynol 465 has been studied. Originally diethylene glycol mono-n-butyl ether was called butyl carbitol and is described, for example, in US Pat. No. 3,291,580. Alternatively, U.S. Pat. No. 2,083,372 discusses the use of ethers of diethylene glycol in ink.

[0005]

However, among the inks having improved permeability to the recording medium as described above,
Even if a nozzle provided with an ink-repellent coating is used for the ease of wetting of the ink, there are some inks in which ejection is not stable and flight deflection occurs. More specifically, in the case of continuous ejection, the ejection direction of the ink droplets is stable, but when the ejection interval (hereinafter referred to as ejection rest time) is several seconds or more, the ejection direction of the ink droplets is The ink becomes unstable and some ink disturbs the recorded image.

Since the ink used in the present invention is an ink having improved penetrability and wettability in the pursuit of a high-quality recorded image among conventional inks, flight bending due to the wettability of the ink is an important subject. Becomes

Therefore, the present invention solves such a problem. An object of the present invention is to prevent the ejection from being stabilized even when a nozzle provided with an ink repellent coating is used due to the ejection rest time, and cause flight bending. An object of the present invention is to provide an inkjet recording method that is effective in preventing flight bending of ink droplets due to wetting of the ink even when an inkjet recording ink is used, and that a good recorded image is obtained.

[0008]

According to the present invention, a part of an ink-repellent coating layer that covers the surface of a nozzle plate is made to enter the inner surface of the nozzle opening, and the nozzle opening is driven by driving a piezoelectric vibrator. In an inkjet recording method for recording by ejecting ink droplets from the ink, at least (A) a dye, (B) a glycol ether having a solubility in water of less than 10% at room temperature, and (C) an organic solvent soluble in water. It is characterized in that the piezoelectric vibrator is driven by a driving voltage that does not eject ink droplets from the nozzle openings when ink is not ejected using the ink for inkjet recording containing the ink.

[0009]

Function: Immediately after the ink droplets are ejected, the nozzle openings are uniformly wet, and when ejected continuously, the ejection direction is stable and no flight bending occurs. However, if the discharge pause time exceeds a certain time (several seconds), the effect of the ink repellent coating layer makes the nozzle openings non-uniform, resulting in unstable discharge direction and flight bending. Therefore, when the piezoelectric vibrator is driven with a drive voltage that does not eject ink droplets from the nozzle openings during non-ejection, the meniscus of the nozzle openings oscillates and maintains a uniform wet state. It is stable and can prevent flight bending.

[0010]

EXAMPLES The ink jet recording ink used in the present invention will be described below.

In the ink used in the present invention, when (A) a dye, (B) a glycol ether having a solubility in water of less than 10% at room temperature and (C) a water-soluble organic solvent are blended and dissolved, an ink is prepared. As components, additives such as antiseptics, antioxidants, conductivity adjusting agents, pH adjusting agents, viscosity adjusting agents, surface tension adjusting agents, oxygen absorbers, nozzle clogging preventing agents and the like can be appropriately used.

(A) Dyes The dyes include water-soluble dyes and oil-soluble dyes.
Water-soluble dyes are easy to handle, have a wide variety of safety and variety, and examples thereof include direct dyes, acid dyes, basic dyes, reactive dyes, and food dyes. The water-soluble dye C.I. I. Direct dye C. I. Direct Black 2, 4, 9, 11, 14,
17, 19, 22, 27, 32, 36, 41, 48, 5
1, 56, 62, 71, 74, 75, 77, 78, 8
0, 105, 106, 107, 108, 112, 11
3, 117, 132, 146, 154, 168, 17
1, 194, C.I. I. Direct Yellow 1, 2, 4,
8, 11, 12, 24, 26, 27, 28, 33, 3
4, 39, 41, 42, 44, 48, 50, 51, 5
8, 72, 85, 86, 87, 88, 98, 100, 1
10, 127, 135, 141, 142, 144, C.I.
I. Direct Orange 6, 8, 10, 26, 29, 3
9, 41, 49, 51, 62, 102, C.I. I. Direct Red 1, 2, 4, 8, 9, 11, 13, 15, 1
7, 20, 23, 24, 28, 31, 33, 37, 3
9, 44, 46, 47, 48, 51, 59, 62, 6
3, 73, 75, 77, 79, 80, 81, 83, 8
4, 85, 87, 89, 90, 94, 95, 99, 10
1, 108, 110, 145, 189, 197, 22
4, 225, 226, 227, 230, 250, 25
6, 257, C.I. I. Direct violet 1,7,
9, 12, 35, 48, 51, 90, 94, C.I. I. Direct Blue 1, 2, 6, 8, 12, 15, 22, 2
5, 34, 69, 70, 71, 72, 75, 76, 7
8, 80, 81, 82, 83, 86, 87, 90, 9
8, 106, 108, 110, 120, 123, 15
8, 163, 165, 192, 193, 194, 19
5, 196, 199, 200, 201, 202, 20
3,207,218,236,237,239,24
6, 258, 287, C.I. I. Direct Green 1,
6, 8, 28, 33, 37, 63, 64, C.I. I. Direct Brown 1A, 2, 6, 25, 27, 44, 5
8, 95, 100, 101, 106, 112, 173,
194, 195, 209, 210, 211, acid dyes C.I. I. Acid Black 1, 2, 7, 16, 17, 2
4, 26, 28, 31, 41, 48, 52, 58, 6
0, 63, 94, 107, 109, 112, 118, 1
19, 121, 122, 131, 155, 156, C.I.
I. Acid Yellow 1, 3, 4, 7, 11, 12, 1
3, 14, 17, 18, 19, 23, 25, 29, 3
4, 36, 38, 40, 41, 42, 44, 49, 5
3, 55, 59, 61, 71, 72, 76, 78, 7
9, 99, 111, 114, 116, 122, 135,
142, 161, 172, C.I. I. Acid Orange 7, 8, 10, 19, 20, 24, 28, 33, 41,
45, 51, 56, 64, C.I. I. Acid Red 1,
4, 6, 8, 13, 14, 15, 18, 19, 21, 2
6, 27, 30, 32, 34, 35, 37, 40, 4
2, 44, 51, 52, 54, 57, 80, 82, 8
3, 85, 87, 88, 89, 92, 94, 97, 10
6, 108, 110, 111, 114, 115, 11
9,129,131,134,135,143,14
4, 152, 154, 155, 172, 176, 18
0, 184, 186, 187, 249, 254, 25
6, 289, 317, 318, C.I. I. Acid Violet 7, 11, 15, 34, 35, 41, 43, 4
9, 51, 75, C.I. I. Acid Blue 1, 7, 9,
15, 22, 23, 25, 27, 29, 40, 41, 4
3, 45, 51, 53, 55, 56, 59, 62, 7
8, 80, 81, 83, 90, 92, 93, 102, 1
04, 111, 113, 117, 120, 124, 12
6, 138, 145, 167, 171, 175, 18
3, 229, 234, 236, 249, C.I. I. Acid Green 3, 9, 12, 16, 19, 20, 25, 2
7, 41, 44, C.I. I. Acid Brown 4, 14, basic dye C.I. I. Basic Black 2, 8, C.I. I. Basic Yellow 1, 2, 11, 14, 21, 32, 36,
C. I. Basic Orange 2, 15, 21, 22,
C. I. Basic Red 1, 2, 9, 12, 13, 3
7, C.I. I. Basic Violet 1, 3, 7, 1
0, 14, C.I. I. Basic Blue 1, 3, 5, 7,
9, 24, 25, 26, 28, 29, C.I. I. Basic green 1, 4, C.I. I. Basic brown 1, 1
2. Reactive dye C.I. I. Reactive Black 1, 3, 5, 6, 8, 1
2, 14, C.I. I. Reactive Yellow 1, 2, 3,
12, 13, 14, 15, 17, C.I. I. Reactive Orange 2, 5, 7, 16, 20, 24, C.I. I. Reactive Red 6, 7, 11, 12, 15, 17, 2
1, 23, 24, 35, 36, 42, 63, 66, 8
4, 184, C.I. I. Reactive Violet 2,
4, 5, 8, 9, C.I. I. Reactive blue 2, 5,
7, 12, 13, 14, 15, 17, 18, 19, 2
0, 21, 25, 27, 28, 37, 38, 40, 4
1, C.I. I. Reactive Green 5, 7, C.I. I. Reactive Brown 1,7,16, food dye C.I. I. FOOD BLACK 1, 2, C.I. I. FOOD YELLOW 3, 4, 5, C.I. I. Hooded 2,3,7,9,
14, 52, 87, 92, 94, 102, 104, 10
5, 106, C.I. I. Hood violet 2, C.I. I.
FOOD BLUE 1, 2, C.I. I. There are a few greens.

As other dyes, Kayaset Black 009A manufactured by Nippon Kayaku Co., Direct Deep Black XA, Direct Special Black AXN, Special Black SP Liquid manufactured by Bayer, Biscript Black SP Liquid, Revasseur Turquoise Blue KS-6.
GLL, pyranine, JI. BK-2, JI. BK-3, Orient Chemical Co., JPK-81L, JPX-127L, JPK-139,
C. I. Flowcent Brightening Agent 1
4, 22, 24, 32, 84, 85, 86, 87, 9
0, 134, 166, 167, 169, 175, 17
6, 177 and the like.

(B) Solubility in water is less than 10% at room temperature. Glycol ether. Solubility in water is less than 10% at room temperature. As a glycol ether, as a result of intensive studies, propylene glycol mono-n-butyl ether and dipropylene glycol mono-n- Butyl ether has been found to be good. The solubility in water was about 5 to 6%, the solubility was further lowered when dyes and other components were added, and the amount added was substantially less than 2%. Therefore, a water-soluble organic solvent can be added so that the solubility can be improved.

(C) Water-Soluble Organic Solvent As a water-soluble organic solvent, it is compatible with water and improves the solubility of a solvent or dye having a low solubility in water, and further penetrates a recording medium such as paper. It is used to improve the property or prevent the nozzle from clogging. Alkyl alcohols having 1 to 4 carbon atoms such as ethanol, methanol, butanol, propanol, and isopropanol, ethylene glycol, diethylene glycol, triethylene glycol, molecular weight 600 or less polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol having a molecular weight of 400 or less, 1,3-butylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentane Diol, 1 Polyhydric alcohols or glycols such as 6-hexanediol, thiodiglycol, glycerin, mesoerythritol, and pentaerythritol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate. , Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-propyl ether, ethylene glycol mono-iso-propyl ether, diethylene glycol mono-iso-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol mono-n-butyl ether, Ethylene glycol mono-t-butyl ether, die Glycol monobutyl -t- butyl ether, triethylene glycol monobutyl ether, 1-methyl-1
-Methoxybutanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-t-butyl ether,
Propylene glycol mono-n-propyl ether, propylene glycol mono-iso-propyl ether,
Glycol ethers such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-iso-propyl ether, formamide, acetamide, dimethyl sulfoxide, sorbit, sorbitin, acetin. , Diacetin, triacetin, sulfolane, etc., which can be appropriately selected and used. The amount used is preferably 1 to 60% by weight based on the total amount of the ink, and the solubility in water to be added is less than 10% at room temperature. It is necessary to add an amount such that the glycol ether does not cause phase separation. If the propylene glycol mono-n-butyl ether and dipropylene glycol mono-n-butyl ether as the glycol ether is less than 3% by weight, the penetrability is insufficient, and if it is 30% by weight or more, oily phase separation easily occurs as an aqueous ink. In addition, the viscosity increases and uniform printing becomes difficult, which is not preferable. A more preferable addition amount is 5 to 10% by weight.

Further, in order to further control the permeability of this ink system, or the solubility in water is 10% at room temperature.
It is also possible to add a surfactant as a solubilizing agent for the glycol ether of less than. The surfactant to be added is preferably a surfactant having good compatibility with the ink system shown in the present embodiment, and among the surfactants, those having a relatively large molecular weight and high permeability and stability are preferable. Examples thereof include anionic surfactants, amphoteric surfactants, cationic surfactants and nonionic surfactants.

As the anionic surfactant, alkyl sulfocarboxylate, α-olefin sulfonate, polyoxyethylene alkyl ether acetate, N-acyl amino acid and its salt, N-acyl methyl taurine salt, alkyl sulfate polyoxy Alkyl ether sulfate, alkyl sulfate polyoxyethylene alkyl ether phosphate,
Rosin acid soap, castor oil sulfuric acid ester salt, lauryl alcohol sulfuric acid ester salt, alkylphenol type phosphoric acid ester, alkyl type phosphoric acid ester, alkylallyl sulfonate, diethyl sulfosuccinate, diethylhexyl sulfo succinate, dioctyl sulfo succinate, etc. Is mentioned.

Examples of the cationic surfactant include a 2-vinylpyridine attractant and a poly-4-vinylpyridine attractant.

Examples of the amphoteric surfactant include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine, polyoctylpolyaminoethylglycine and others. Examples include imidazoline derivatives.

As the nonionic surfactant, polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether. , Ether such as polyoxyethylene alkyl ether, polyoxyalkylene alkyl ether, polyoxyethylene oleic acid, polyoxyethylene oleic acid ester, polyoxyethylene distearate ester, sorbitan laurate, sorbitan monostearate, sorbitan monooleate Ester system such as sorbitan sesquioleate, polyoxyethylene monooleate, polyoxyethylene stearate 2,4,7,9-tetramethyl -5
-Decyne-4,7-diol, 3,6-dimethyl-4-
Octyne-3,6-diol, 3,5-dimethyl-1-
There are acetylene glycols such as hexyne-3-ol (eg, Nisshin Chemical Surfinol 104, 82, 465, etc.) and the like.

Further, for example, as a preservative / antifungal agent, sodium benzoate, pentachlorophenol sodium,
2-Pyridinethiol-1-oxide sodium, sodium sorbate, sodium dehydroacetate, 1,2
-Dibenzisothiazolin-3-one (Proxel CRL, Proxel BDN, Proxel GXL, Proxel XL-2, Proxel TN, manufactured by ICI) may be added.

Alternatively, amines such as diethanolamine, triethanolamine, propanolamine and morpholine as pH adjusters, inorganic salts such as potassium hydroxide, sodium hydroxide and lithium hydroxide, ammonium hydroxide and quaternary ammonium hydroxide. Compounds (tetramethylammonium, etc.), carbonates such as potassium carbonate, sodium carbonate, lithium carbonate and other phosphates, or N-methyl-2-pyrrolidone, urea, thiourea,
There are ureas such as tetramethylurea, alohanates and alohanates such as methylallohanate, and burettes such as burette, dimethyl buret and tetramethyl buret.

Further, as the viscosity modifier, there are polyvinyl alcohol, hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, polyacrylate, polyvinyl pyrrolidone, gum arabic starch and the like.

Ink Examples of Inkjet Recording Inks Used in the Present Invention, Incorporating (A) Dye, (B) Glycol Ether Having Solubility in Water of Less than 10% at Normal Temperature, and (C) Water-Soluble Organic Solvent Shown in. The ink examples shown in Table 1 were excellent in the quality of a recorded image on plain paper, particularly recycled paper which has been frequently used in recent years due to environmental problems and the like.

[0025]

[Table 1]

Next, details of the ink jet recording method of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of an ink jet recording head applied to the ink jet recording method of the present invention. In this ink jet recording head, a pressure generating chamber 6 is formed by a nozzle plate 3 provided with an ink repellent coating layer 1 and a nozzle opening 2 formed therein, a spacer member 4 and a vibrating plate 5, and the pressure generating chamber 6 is formed. Ink is supplied from the ink supply port 7 on one side, and the vibration plate 5 is pressed by the expansion and contraction of the piezoelectric vibrator 8 to eject ink droplets from the nozzle opening 2. As the ink repellent coating layer 1,
Eutectoid plating of nickel and polytetrafluoroethylene, which has both excellent water repellency and durability, is applied.

2 to 6 are enlarged views of the nozzle opening 2 of FIG. 1, and FIGS. 2 to 5 show a series of ejection of ink droplets. FIG. 6 shows the ink jet recording method of the present invention. A series of situations in the case of

FIG. 2 shows a series of ejection of ink droplets when the ink of the ink comparative example is used. Figure 2
(A) shows the initial state before the start of ejection, and the ink-repellent coating layer portion 1-A of the nozzle opening 2 is not wet because it repels the ink. FIG. 2B shows a state in which a negative pressure is generated in the pressure generating chamber 6 due to the reduction of the piezoelectric vibrator 8 and the meniscus 9 is pulled in. FIG. 2C shows a state where a positive pressure is generated in the pressure generating chamber 6 due to the expansion of the piezoelectric vibrator 8 and the ink is pushed out from the nozzle opening 2. The ink receives a uniform force from the entire ink repellent coating layer portion 1-A, and the ejection direction is stabilized. FIG. 2D shows a state in which the ejection has been completed. The ink repellent coating layer portion 1-A instantaneously repels the ink, and the meniscus 9 returns to the same state as in FIG.

FIG. 3 shows a series of ejection of ink droplets when the ink of the ink example is used. FIG.
(A) shows the initial state before the start of ejection, and the ink-repellent coating layer portion 1-A of the nozzle opening 2 is not wet because it repels the ink. FIG. 3B shows a state in which a negative pressure is generated in the pressure generating chamber 6 due to the contraction of the piezoelectric vibrator 8 and the meniscus 9 is pulled in. FIG. 3C shows a state in which a positive pressure is generated in the pressure generating chamber 6 due to the expansion of the piezoelectric vibrator 8 and the ink is pushed out from the nozzle opening 2. The ink is ejected by receiving an even force from the entire ink repellent coating layer portion 1-A. FIG. 3D shows a state where the ejection has been completed. However, unlike the case of FIG. 2D, the ink repellent coating layer portion 1-A remains wet immediately after ejection, and the meniscus 9 is at a position different from that of FIG. 3A.

FIG. 4 shows a series of states in which ink droplets are ejected when the ink of the ink example is continuously ejected. FIG. 4A shows the same state as FIG. 3D. FIG. 4B shows a state in which a negative pressure is generated in the pressure generating chamber 6 due to the contraction of the piezoelectric vibrator 8 and the meniscus 9 is drawn in. The ink repellent coating layer portion 1-A is in a uniformly wet state.

FIG. 4C shows a state where positive pressure is generated in the pressure generating chamber 6 due to the expansion of the piezoelectric vibrator 8 and ink is pushed out from the nozzle opening 2. The ink is ejected by receiving an even force from the entire ink repellent coating layer portion 1-A. FIG.
(D) shows the state where the ejection is completed. In the continuous discharge, since the series of operations shown in FIG. 4 is repeated, the discharge direction is stable and the flight curve does not occur.

FIG. 5 shows a series of ejection of ink droplets when the ejection pause time is provided using the ink of the ink embodiment. FIG. 5A shows a state in which the ink is gradually repelled from the ink repellent coating layer portion 1-A from the state of FIG. 3D and the wetting becomes uneven. FIG. 5B shows a state in which a negative pressure is generated in the pressure generating chamber 6 due to the contraction of the piezoelectric vibrator 8 and the meniscus 9 is drawn in. The ink repellent coating layer portion 1-A is in a nonuniformly wet state. FIG. 5 (c) shows
A positive pressure is generated in the pressure generating chamber 6 due to the expansion of the piezoelectric vibrator 8,
The state where ink is pushed out from the nozzle opening 2 is shown. The ink is ejected by receiving an uneven force from the wet portion and the non-wet portion of the ink repellent coating layer 1-A. FIG. 5D shows a state in which the ejection has been completed. The ink droplets change their ejection direction depending on the balance of the force received from the ink-repellent coating layer portion 1-A, causing flight bending. If the discharge suspension time is long (several minutes or more), the meniscus 9 is in the same state as in FIG. 3 (a), and flight bending does not occur.

FIG. 6 shows a series of states when the ink jet recording method of the present invention is performed using the ink of the ink example. FIG. 6A shows the same state as FIG. 5A. 6B and 6C show how the meniscus 9 swings when the piezoelectric vibrator 8 is driven by a drive voltage that does not eject ink droplets from the nozzle openings 2. In this way, the piezoelectric vibrator 8 is driven by the drive voltage that does not eject ink droplets from the nozzle openings 2, and the ink-repellent coating layer portion 1 is formed until the next ejection.
By making -A uniformly wet, stable ejection equivalent to the case shown in FIG. 4 can be obtained. The driving of the piezoelectric vibrator for the method of preventing the flight bending of the ink droplets may be performed only when necessary so that the flight bending of the ink droplets does not occur. Therefore, the driving of the piezoelectric vibrator during non-ejection may be always performed, or may be performed as needed before ejection.

As a specific example of the ink jet recording method described above, Table 2 shows method examples and method comparative examples. Method Two methods were used to drive the piezoelectric vibrator during non-ejection of the method example. The symbol A in Table 2 represents a case where the device is always driven during non-ejection, and the symbol B is 100 immediately before ejection.
It represents the case of driving 0 times, and the symbol C represents the case of not driving. As the driving condition of the piezoelectric vibrator during non-ejection,
The drive voltage is 16% of the discharge voltage, and the drive cycle is 10 kHz.
I went in. Therefore, the time required to drive 1000 times immediately before ejection is only 0.1 seconds. In Table 2, the discharge pause time of 0 seconds (method comparative example 1) indicates the case where continuous discharge was performed.

[0036]

[Table 2]

Next, Table 3 shows the results of evaluating the ejection stability by combining the ink and the recording method. As the evaluation items, the presence or absence of flight bending due to wetting, and the presence or absence of ink leakage or overflow from the ink openings are evaluated. In Table 3, ◯ represents the case without, and × represents the case with. . In the combination of the ink example and the method example, the ink repellent coating layer portion of the nozzle opening is kept uniform by the swing of the meniscus corresponding to FIG. 6, and the ejection corresponding to FIG. 4 is performed. Ink Example and Method Comparative Example 1 (continuous ejection)
In the combination of, the ejection corresponding to FIG. 4 is performed. In the combination of the ink example and the method comparison example 4, the ejection corresponding to FIG. 3 is performed. As the ejection pause time becomes longer, the ink-repellent coating layer is not wetted by the effect of the ink-repellent coating layer, so that flight bending does not occur. However, the method comparative example 4 is not practical because it has to wait several minutes each time the ejection is stopped. In the methods of Comparative Examples 5 to 7 in which the ink repellent coating layer was not applied, there was no flight bending due to wetting, but there was ink leakage and overflow from the ink openings. In the combination of the ink example and the method comparative examples 2 to 3, flight bending due to wetting occurs, and ejection corresponding to FIG. 5 is performed.

[0038]

[Table 3]

The present invention should not be considered to be limited to these examples, and various modifications can be made without departing from the spirit of the present invention.

[0040]

As described above, according to the present invention, flight deflection of ink droplets peculiar to an ink jet recording ink having a high penetrability capable of obtaining a high-quality recorded image on plain paper used in the present invention. Can be prevented and a good recorded image can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of an inkjet recording head.

FIG. 2 is an explanatory diagram showing a series of states in which ink droplets are ejected when the ink of the ink comparative example is used.

FIG. 3 is an explanatory diagram showing a series of states in which ink droplets are ejected when the ink of the ink example is used.

FIG. 4 is an explanatory diagram showing a series of states in which ink droplets are ejected when continuous ejection is performed using the ink of the ink example.

FIG. 5 is an explanatory diagram showing a series of states in which ink droplets are ejected when the ejection pause time is provided using the ink of the ink example.

FIG. 6 is an explanatory diagram showing a series of states when the ink jet recording method of the present invention is performed using the ink of the ink example.

[Explanation of symbols]

 1 Ink repellent coating layer 1-A Ink repellent coating layer portion of ink opening 2 Nozzle opening 3 Nozzle plate 4 Spacer member 5 Vibration plate 6 Pressure generating chamber 7 Ink supply port 8 Piezoelectric vibrator 9 Meniscus

Claims (3)

[Claims] 1. A part of an ink repellent coating layer that covers the surface of a nozzle plate is made to enter the inner surface of a nozzle opening, and an ink droplet is ejected from the nozzle opening by driving a piezoelectric vibrator. In an inkjet recording method for recording, at least (A) a dye, (B) a glycol ether having a solubility in water of less than 10% at room temperature,
(C) An inkjet recording method using an inkjet recording ink containing an organic solvent that dissolves in water to drive a piezoelectric vibrator with a drive voltage that does not eject ink droplets from a nozzle opening when not ejecting . 2. The ink jet recording method according to claim 1, wherein the glycol ether is propylene glycol monobutyl ether and / or dipropylene glycol monobutyl ether. 3. The ink jet recording method according to claim 1, wherein the ink repellent coating layer is eutectoid plating of nickel and polytetrafluoroethylene.